What I don't get is why people don't try things - let's be honest here - that line 6 has a ¼" output - and plugging this into the interface should work fully home, and if you were unlucky enough to find it didn't, the half pulling out the plug would!
When I was a teenager, I'd happily sacrifice a couple of cables, and twist the wires together to make odd items talk to each other. When I knew little, I knew one would hum when touched, so connecting sources to this usually made some kind off noise - and trial and error rarely failed. Then you twisted the wires tighter, wrapped it in tape and used it for years sometimes. Later when I could solder properly, many of these working bodges got fixed - but I found one the other day, still wrapped in the tape, and it still worked!!
In so many topics, you get people asking before ordering cables, and they order just one - when a few cheap cables with all kinds of ends get you out of trouble fast!